SUPERB QUALITY & SILENT OPENOur hidden door hinges are made of high-quality zinc and alloy materials, and wear-resistant nylon gaskets are added to be silent and wear-resistant, ensuring long-term sturdiness, durability, silence and no abnormal noise.REQUIRED READINGProduct Size: 7 x 2.9 x 1.1 inch, Two Hinges Support: 178 pounds, Door Opening Angle: 180 degree, Door Thickness > 35-40mm, Door Width < 850mmPlease check that the hinge size fits the door and frame before purchasing3D ADJUSTABLE DESIGNvertical 3mm, horizontal 2mm and depth 1 mm. With our adjustable design, you can fine-tune the hinges for perfect alignment. The hinges can be adjusted without removing the door.COMPLETELY HIDDEN DESIGNHidden hinges for doors can be used to create invisible doors, folding doors, and other feature walls. Whether the door opens internally or externally, the door closes with no hinges visible indoors or outdoors. Our hidden door hinge means you can use this heavy duty hinge whether your door is a left hand door or right hand door. Seamless hidden hinges make your door look stylish and sophisticated.EASY TO INSTALLThis secret door hinge comes with a complete kit. No additional purchase is required. Simply cut slots in the door and frame and install the hinges, fine-tuning the position of the hinges to complete the installation.